The invention relates to a mixture comprising diacetyl tartaric acid esters of mono- and diglycerides based on C12 to C22 fatty acids. Diacetyl tartaric acid esters of mono- and diglycerides based on C12 to C22 fatty acids are generally known as baking ingredients for baked products more in particular for yeast-leavened products such as bread (especially white bread), tin bread, rolls, hard rolls, German crispy rolls, buns, rusks etc. These esters are able to improve the products in various respects as good leavening expressed as specific volume, even pores and acceptable crustiness. Also they are known to improve the properties of dough such as its stability and rheology and are therefore often referred to as dough conditioners. The esters are further used in baking aids and in improved flour. The EC number of mixtures of diacetyl tartaric acid esters of mono- and diglycerides based on C12 to C22 fatty acids is E 472e (DATEM).
The art has long described mixtures comprising diacetyl tartaric acid esters of mono- and diglycerides based on C12 to C22 fatty acids and their preparation e.g.
U.S. Pat. No. 2,236,516 (Frank J. Cahn et al) is an early patent specification disclosing products obtained by reacting diacetyl tartaric acid with glyceryl monostearate.
U.S. Pat. No. 2,689,797 (Morris H. Joffe) discloses improvements in bread obtained by the incorporation of diacetyltartaric esters of unsaturated and partially saturated mono and/or partial glycerides.
U.S. Pat. No. 2,938,027 (Martell M. Gladstone) discloses the reaction between mixtures of acetylated anhydrides of food acids such as e.g. tartaric acid containing 4 to about 95% of diacetylated tartaric acid and e.g. free acetic anhydride with partial glycerides of fatty acids to obtain improved products.
U.S. Pat. No. 3,443,969 (Nobuo Nakejima et al) discloses diacetyltartaric esters of purified (molecular distilled) monoglycerides of vegetable oils.
GB-A-1 220 488 (Aktieselskabet Grindstedvaerket) discloses the preparation of an emulsifier obtained by reacting e.g. distilled glycerol monostearate with diacetyl tartaric anhydride in certain molar ratios followed by prolonged heating to 135-190xc2x0 C. as to obtain by polymerisation a satisfactory oil-in-water emulsifier of higher molecular weight, which apparently contains polymeric esters due to splitting off acetic acid and water.
GB-A-1 344 518 (Dynamit Nobel A.G.) discloses solid acetyltartaric esters obtained by reacting at least partially acetylated tartaric acid with partial glycerides containing 55-65% monoglyceride and an iodine value below 5 which contain per mole of partial glyceride 0.91-1.8 mole tartaric acid residues and 1.8-3.4 mole acetic acid residues. These esters free flowing powders whereas the traditional esters have a waxy or honey-like consistency. This difference in physical properties is due to the fact that these powders contain appreciable quantities of say about 0.3 mol % of glyceride esters of monoacetyl tartaric residues and/or even non-acetylated tartaric acid residues. Conventional acetylated tartaric acid esters of mono- and/or diglycerides are mono- and/or diglyceride esters of (almost) pure diacetylated tartaric acid (anhydride). The products according to the present invention are also very low in esters of monoacetylated tartaric acid (anhydride).
Although the current diacetyl tartaric acid esters of mono- and diglycerides based of C12 to C22 fatty acids are valuable products they are often somewhat defective as to:
1. specific volume of the baked product obtained;
2. stability as to leavening under the influence of yeast;
3. stability properties of the dough prepared.
It is an object of the present invention to provide a mixture comprising diacetyl tartaric acid esters of mono- and diglycerides based on C12 to C22 fatty acids yielding a performance which is improved in at least one of the properties mentioned above. Moreover the present invention also provides a process for the preparation of the mixtures of the diacetyl tartaric acid esters of mono- and diglycerides based on C12 to C22 fatty acids according to the present invention by reaction of diacetylated tartaric acid anhydride and mono- and diglycerides C12 to C22 fatty acids at a relatively low temperature combined with a short time of reaction which is more economic than most of the current processes.
The invention therefore provides in a first embodiment a mixture comprising diacetyl tartaric acid esters on mono- and diglycerides based on C12 to C22 fatty acids which mixture comprises diacetyl tartaric acid glycerol monoesters containing: (A) one fatty acid group, one diacetylated tartaric acid monoester group and a free hydroxyl group and (B) one fatty acid group and two diacetylated tartaric acid monoester groups in which
1. the concentration of (A) above in the total mixture obtained by dividing the molar amount of (A) by the sum of the molar amounts of all components in the mixture and multiplying by 100 is at least 45%, preferably at least 50% and that
2. the fraction obtained by dividing the molar amount of (A) above by the combined molar amounts of (A) and (B) taken together is at least 0.70, preferably at least 0.72 and in which the molar amounts are determined by the NMR method herein described.